tikka t3 284win vs 280 vs 280ai

[Gspkora]

hi all
I am going to rechamber my tikka t3 in 7mm-08 to one of the above calibers
but i am stuck on what one .
what would you go for and why and what performance can i expect from each keeping in mind the factory 570mm barrel (22.44").
and i have the long action bolt stop and mag ready to go.

 

[RevJim]

The standard 280 will do everything you want in that 22" barrel. The 284 'can" be a bear to feed properly and the 280AI will only gain you about 50fps or so in that barrel. I base this on my use of a 6.5/284 when it was a wildcat, that last round just would not feed right. I had a 22" 280 reamed to the AI back in early '90s, sure enough, 2950 over the 2900 I was getting before with the Nosler 150BT. I only got 2800 (which isn't bad) with the Speer 160. with todays modern, newer powders, you have the rifle set up to seat your bullets out to 3.5 or so, you are "in the berries"! Good luck to you Pard.

 

[PGJPJ]

I'm running a 280ai with 24" barrel. Using RL26 and 168 grain bullets, I can get 2925 comfortably. 2950 starts to show pressure.

With a bit shorter barrel, I might be leaning for a standard 280, but no good reason why.

 

[Gspkora]

thanks for your reply's
i will be using high b.c projectiles so how do you think i will go for room in the mag with the .280 i know i will have plenty with the .284?

 

[AZShooter]

If your tikka has the same magazine as my friends T3 it is a single stacker so the 284 Win shouldn't have a feeding issue. To be certain see if you can try some.

I am using a 284 win with the 168 Berger VLD set with heel of bullet even with neck shoulder junction. OAL is 3.050" You should have no problem with bullet fit in a LA magazine.

I was going to suggest you try the 284 win earlier today but I didn't do it when I discovered Bullets.com doesn't have any lots of the new Norma 284 win brass smaller than 1000 pieces. A long search for Winchester brass was fruitless. If the rifle is in the works and there is a wait, perhaps the smaller lots will show at bullets.com by then. Otherwise you would have to find old Win brass somewhere or better yet neck up some 6.5-284 lapua brass. Best choice obviously is the new Norma brass.

See link on the Norma brass:

Norma to Make 6mm Dasher and .284 Win Brass for Bullets.com « Daily Bulletin


The 284 Winchester reamer will clean up the 7-08 chamber with no setback.

Only issue right now is brass. Getting the brass is paramount before you build.

I had a custom reamer made with the intention of turning the old Winchester brass I had on hand. Reamer has a .315'' neck. Throat is a 1 degree 1/2 min angle and bullet is sitting into the lands approx. .010" The accuracy load is 51 gr of RL-17 with Fed 210 match primer for velocity of 2835 fps with 24" barrel.

Good luck on your choice.

 

[Gspkora]

thanks az shooter
the brass is also a problem i will have to deal with if i go with.284
but .280 and .280ai brass is in stock at my local store.
I am leaning towards the .284 win think the short case will be better in the 22" barrel

 

[Deleted member 25294]

thanks for your reply's
i will be using high b.c projectiles so how do you think i will go for room in the mag with the .280 i know i will have plenty with the .284?

If you go with the 280 you wont be able to seat the high BC bullets out very far at all. I was looking at doing a 6.5-06 in a Tikka, I loaded a dummy round with a 140 berger VLD and it didn't even come close to fitting in the mag.
The 284 would probably be a better choice in a Tikka

 

[TOM H]

thanks az shooter
the brass is also a problem i will have to deal with if i go with.284
but .280 and .280ai brass is in stock at my local store.
I am leaning towards the .284 win think the short case will be better in the 22" barrel

The 284 and 280 have almost same case capacity.

I shoot 284 on long action and 280AI both have 27" barrels. Me I do the 280AI.

 

[Buska]

I don't have any experience with the 284 but have a 280AI and like it pretty well. It's a 24" barrel and wish it were 26"+. You can get a Douglas "premium air gauged" barrel from Red Hawk for about $280 or so...I'd do either but would get a longer tube of you can. That's my opinion anyway have fun with whatever you do!

 

[Gspkora]

what sort of velocity are you getting out of your .284
I love the 7mm-08 its chambered in but the case capacity with high b.c pulls is a bit restricting im not expecting amazing velocity out of the new chamber but enough for a bit
more grunt for those longer shots.
anyone with a .280 or 284 in 22" barrel know what speeds you are getting with the 160g and over pills

 

[bigngreen]

The Tikka action shines in medium length chambering like the 284 or WSM's, once you start going even the 06 length case seating high BC bullets you single sledding them. A 284 or 7-300 WSM on the Tikka would be the only way I'd build it. Feeding from the mag is also a non issue in either with the Tikka mag design.

 

[RevJim]

As I mentioned, I started out using the 284 Win brass to neck down for the 6.5/284. Later in life, when it was standardized, I tried both the Hornady and the Norma brass, and I found them both much softer than the Winchester. No biggy, just saying. I haven't seen any 284 Win brass in years myself. I don't know much about Tikkas, admittedly, but there is just so much one can do with a 22" barrel. I'm not sure how much you could get from a 7mmWSM, but I haven't seen much of that ammo, nor brass in a very long while. I had a 7mm Express (280) in 22" and I got 2750 with the Nosler 168 ABLR. It had a long throat, was in a Mod 700 long action, of course. All it will cost you is a bit of time and money to experiment, heck, you might end up with a winning combo! One last mention...the 7mm SAUM "supposedly" will give 280 velocities...if you can find brass, that may work better than the 284.

 

[TOM H]

what sort of velocity are you getting out of your .284
I love the 7mm-08 its chambered in but the case capacity with high b.c pulls is a bit restricting im not expecting amazing velocity out of the new chamber but enough for a bit
more grunt for those longer shots.
anyone with a .280 or 284 in 22" barrel know what speeds you are getting with the 160g and over pills

The Berger 168gr VLD bullet is appr 1.450" long and 284 case is 2.170" and case body length is 1.775" and from the start of shoulders to case mouth is .395" Depending how you have it throated long action you could be 3.200" which would be pretty close to SAAMI Spec for 280AI @ 3.330".

If you need just little more why not do 7-08AI then save some money for 24" barrel.

 

[Gspkora]

I thought about the 7mm08ai but dont think would be enough difference in performance to justify the cost of fireforming brass
and if i get 2-300fps gain with .284win /280 even with a 22" barrel which i think is easly done.
this would take me out to 1000yards with over 1000ft-lb
my current 7mm08 runs out of puff at 700yard